This security update resolves vulnerabilities in Windows that could allow remote code execution in a host context if a specially crafted application is run by an authenticated and privileged user on a guest virtual machine that is hosted by Hyper-V. An attacker must have valid logon credentials for a guest virtual machine to exploit this vulnerability.

This one is critical. So do not delay long after your smoke testing of this patch.You have some time to act but don’t wait too long:

Microsoft received information about this vulnerability through coordinated vulnerability disclosure. When this security bulletin was originally issued Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers.

With November 2012 Patch Tuesday having come and gone, the first hotfixes (it’s a cumulative update) related to Windows Server 2012 are available. These are relevant to both Hyper-V & Failover clustering (Scale Out File Server) There is also an older hotfix that has been brought to our attention that related to certain versions Windows Server 2008/R2 domain controllers,which is also important for Windows Server 2012 Clustering. None of these are urgent/critical and only apply in specific circumstances but it’s good to keep up with these and protect your environment..

Windows 8 and Windows Server 2012 cumulative update: November 2012

http://support.microsoft.com/kb/2770917: A collection of small changes – for HA VMs (Hyper-V on Cluster) there are three minor CSV file system fixes in this Hotfix : Improves clustered server performance and reliability in Hyper-V and Scale-Out File Server scenarios. Improves SMB service and client reliability under certain stress conditions.

Error code when the kpasswd protocol fails after you perform an authoritative restore: “KDC_ERROR_S_PRINCIPAL_UNKNOWN”

http://support.microsoft.com/kb/976424: Install on every domain controller running Windows Server 2008 Service Pack 2 or Windows Server 2008 R2 in order to add a Windows Server 2012 failover cluster. This is included in Windows Server 2008 R2 Service Pack 1. So just see if you need this fix in your environment or not.

I’m happy to see Microsoft acting fast on these issues,, even if not critical, to serve & protect their customers deployments.